It also seems strange to put and adjective 有能な (capable) before 人材 (capable person). This is a sentence from anime series so I guess all kinds of slang is possible.
The role of のも is particularly well explained in the answers that Jimmy Yang linked to, so I will not repeat that.
As for putting an adjective 有能な before 人材, I would argue that the core meaning of the word 人材 is the second meaning listed in https://jisho.org/search/%E4%BA%BA%E6%9D%90 :
- capable person; talented person
- human resources; personnel
As the meanings listed for 人材派遣 (temporary employee placement) and 人材紹介会社 (employment agency; staffing agency; personnel placement agency) imply, I argue that the core concept of 人材 is "human resource".
人材 does have a connotation of that person being capable. Hence, as aguijonazo pointed out in the comment, 無能な人材 does look strange; but since it is only a connotation, it is completely acceptable to say 有能な人材, 優秀な人材 or エリート人材.
There is an interesting semi-joke related to this: 「人財」「人材」「人在」「人罪」. It is a cliché repeated in business-related articles such as https://jtb-hrsolution.jp/hrsupplement/evp/65 :
- 「人材」: the usual word for "human resource"
- 「人財」: human resource so capable that it is equatable to a treasure (財宝)
- 「人在」: someone who simply exists (存在) in the company. They might do their job but mediocrely or without any passion; in other cases, they might simply sit in the office and serve very little (In Japan, it is quite hard to legally fire a person)
- 「人罪」: someone who deals damage to the company or the organization, or even commits crimes (罪) for their own benefit